Choose the best answer

Find the answers for the questions 23-26 according to this text
Birdsong is an exceedingly complex and sophisticated communication system. It is produced from the bird's syrinx, a sound box at the junction of the two bronchi, which lead to the lungs. Air from the lungs is passed over membranes in the syrinx, which then vibrate, producing sound waves. Because there are two bronchi with membranes, sound can emanate from each and combine higher in the vocal tract, producing a large variety of sounds.

Complexity in the vocal muscles also translates into more complex songs. Birds sing to defend territory and to attract mates. Some species even sing when pursued by predators to convey how robust they are. On the whole, males sing more than females. The male brown thrasher has command of some 2,000 different songs. Male and female birds sometimes sing duets, and groups of birds may sing together to defend a territory.

Some species are especially adept at mimicry. Some Scottish starlings reproduce the sounds of sheep; some English starlings even mimic city buses.
23. Where is the birdsong produced?

A) in the stomach

B) in the membrane

C) in the throat

D) in the food tract
24. What are the reasons for birds singing?

A) breeding and feeding

B) feeding and defense

C) breeding and protection

D) food and protection

25. Which of these statements is true?

A) Male and female birds never sing together.

B) Complexity of vocal muscles depend on songs.

C) Males sing more than females.

D) Brown thrasher can sing only 200 songs

26. Which type of birds can mimic the sounds of other animals?

A) Syrinx B) Male

C) Scottish starling D) English starling